Method and Apparatus for Preventing the Drive Wheels of an Irrigation Machine from Becoming Stuck in the Mud

ABSTRACT

To prevent the rut-like wheel tracks of an irrigation machine from becoming so deep that the wheels of an irrigation tower can become stuck in mud and water accumulating in the track, a foundation member is inserted into select, potentially troublesome portions of the wheel track to provide support for the wheels during subsequent passes of the machine. In one embodiment the foundation member comprises a generally rectangular pad constructed from synthetic resinous material and designed to be hooked together with other such pads in a chain-like series to provide the length of foundation required. In another embodiment, the foundation member comprises a thinner web or ribbon of preferably synthetic resinous material that may be wound into a coil for storage and cut to length as required. A third embodiment comprises a series of end-to-end pads hingedly interconnected by thinner lines of weakness that may be severed to provide a desired length of foundation member.

TECHNICAL FIELD

This invention relates to large irrigation machines of the type utilizedin watering crops in the field and, more particularly, to a way ofpreventing such machines from becoming stuck in the water and mud indeep wheel tracks created when the machine repeatedly passes throughsoft spots and depressions in the field.

BACKGROUND AND SUMMARY

Center pivot and lateral move irrigation machines have been plagued formany years with the problem of deep wheel tracks caused by repeatedpasses of tower drive wheels over the same path of travel again andagain. While the tracks may be shallow at first, they may becomeprogressively deeper with each pass, and in those areas of the fieldwhere drainage is a problem, the wheel tracks may collect water andbecome so deep that the wheels literally get stuck in the mud. Thisproblem can occur at any of the towers on the machine and at any placein the field such that it takes only one stuck tower to shut down theentire machine. Getting the tower unstuck can be a time-consuming anddifficult process, and consequential irrigation delays during criticalwatering schedules may become costly in terms of potential crop yieldlosses.

The present invention provides a method and apparatus for preventingthis problem. In its broadest aspects, the invention contemplatespreparing a foundation in potentially problematic wheel tracks that thetower wheels can ride upon as the tower traverses the problem area. Itis recognized that the majority of any particular wheel track will notpose a problem; however, after a number of passes by a machine, certainareas of the track may begin to deepen and collect water to such anextent that it becomes apparent this particular area is going causeproblems. At that time, a foundation member in accordance with thepresent invention may be inserted into the track and laid at the bottomthereof in position to be engaged by the tower wheels on their nextpass. One preferred approach contemplates inserting foundation membersimmediately behind the lead wheel of a two-wheeled tower such that thefoundation members are in position to be engaged and pushed down intofinal position by the trailing wheel of the tower. With the foundationmembers in place, the weight of the tower is borne by the foundationmembers as the wheel passes over, and further deepening of the wheeltrack is substantially eliminated.

One embodiment has individual foundation members in the nature of agenerally rectangular pad, preferably constructed of high densityPolyethylene or the like. Each pad has a width that is slightly lessthan the nominal width of the wheel track, so that when the pad isplaced within the track, the sides of the track confine the pad and keepit from moving out of place. Each pad is preferably provided withinterlock structure at its opposite ends so that an appropriate numberof pads can be interlocked end-to-end in a series of sufficient lengthas to provide adequate foundation through the troublesome area.

In another embodiment, the foundation material may be somewhat thinnerand take the form of a ribbon that can be laid down in the track and cutto the desired length. Preferably, the ribbon is sufficiently flexibleas to permit storage in the form of a coil for convenient transport anddispensing. It is further contemplated that the mobile tower itself maybe utilized to carry the supply of foundation members to the troublesite.

In a further embodiment, the foundation material is similar in thicknessto the separate pad embodiment, but each pad is interconnected withadditional such pads in a series by hinging lines of weakness. Thecontinuous string of pads may be conveniently stored in a somewhatflat-sided coil as permitted by the lines of weakness. A string of padsof any desired length may be severed from the rest of the supply at anappropriate line of weakness and laid down in the wheel track to supportthe wheels.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary perspective view of a center pivot irrigationsystem with which the principles of the present invention may beutilized;

FIG. 2 is a top isometric view of one embodiment of foundation member inaccordance with the present invention wherein the member is in thenature of a foundation pad;

FIG. 3 is a bottom isometric view of the foundation pad of FIG. 2;

FIG. 4 is an enlarged, longitudinal cross-sectional view through thefoundation pad of FIG. 2;

FIG. 5 is an isometric view illustrating the manner in which a pair offoundation pads may be interlocked end-to-end, the pads beingillustrated in the initial stage of interlock;

FIG. 6 is an enlarged, fragmentary longitudinal cross-sectional viewthrough the interlocking structure of a pair of the pads in thecondition of FIG. 5;

FIG. 7 is an isometric view of the two foundation pads with theinterlock process partially completed;

FIG. 8 is an enlarged, fragmentary longitudinal cross-sectional view ofthe interlocking structure when the parts are in a conditioncorresponding to FIG. 7;

FIG. 9 is an isometric view illustrating three of the foundation padsfully interlocked to create a series of the pads;

FIG. 10 is a fragmentary, enlarged, longitudinal cross-sectional viewthrough one of the interlocking structures corresponding to the fullyinterlocked condition of the pads in FIG. 9;

FIG. 11 is a fragmentary isometric view illustrating the process ofinstalling an interlocking a pair of the foundation pads within a wheeltrack;

FIG. 12 is a fragmentary longitudinal cross-sectional view of the wheeltrack and interlock process of FIG. 11;

FIG. 13 is an isometric view similar to FIG. 11 but further along in theinstallation process illustrating a series of four of the foundationpads interlocked within the track;

FIG. 14 is a longitudinal cross-sectional view of the wheel track withthe four foundation pads installed as in FIG. 13;

FIG. 15 is an isometric view similar to FIGS. 11 and 13 but showing acompletely installed string of interlocked foundation pads with thetrailing wheel of the irrigation tower riding upon the last fewfoundation pads in the string;

FIG. 16 is a cross-sectional view of the wheel track with the foundationpads and the trailing wheel in the same condition as FIG. 15;

FIG. 17 is a fragmentary, enlarged, transverse cross-sectional viewthrough a typical wheel track with a foundation pad in place and a drivewheel riding on top of the pad to illustrate relationships between theparts under such conditions; and

FIG. 18 is an isometric view of a second embodiment of foundation memberin which the member comprises a ribbon of material that can be stored ina coil and conveniently cut to length before being placed within aproblematic wheel track;

FIG. 19 is an isometric view of a third embodiment of foundation memberin which the member comprises a string of pads hingedly interconnectedin a continuous string by thinner lines of weakness so the string can bestored in a flat-sided coil and severed from the supply in desiredlengths; and

FIG. 20 is an isometric view illustrating how a string of interconnectedpads in accordance with the first embodiment can be easily stripped outof the wheel track at the end of a season of use.

DETAILED DESCRIPTION

The present invention is susceptible of embodiment in many differentforms. While the drawings illustrate and the specification describescertain preferred embodiments of the invention, it is to be understoodthat such disclosure is by way of example only. There is no intent tolimit the principles of the present invention to the particulardisclosed embodiments.

For purposes of example, the present invention has been illustrated inthe drawings, and will hereinafter be described, in connection with acenter pivot irrigation machine. However, it should be apparent to thoseskilled in the art that the principles of the present invention are notlimited to use with a center pivot machine. Indeed, the principles ofthe present invention may be applied with great benefit to lateral movemachines as well.

The center pivot irrigation machine 10 illustrated in FIG. 1 has a long,water-carrying conduit 12 that is supported at spaced locations alongits length by a plurality of mobile towers 14. Conduit 12 is adapted topivot about the upright axis of a supply pipe 16 which is connected to asource of water (not shown) and is supported by a fixed tower 18.Various of types of sprinklers or emitters (not shown) are typicallyprovided along the length of conduit 12 for directing water onto theground in the vicinity of machine 10.

Each mobile tower 14 has, in the illustrated embodiment, a pair ofdriven ground wheels 20 and 22 that propel the tower 14 through thefield. Ground wheels 20, 22 are driven by an electric motor 24 or othersuitable means on the tower. Wheels 20, 22 are in fore-and-aft alignmentwith one another such that wheel 22 trails directly behind and inalignment with leading wheel 20.

As the towers 14 move through the field in repeated passes, their groundwheels 20, 22 leave wheel tracks 26 that can become progressively deeperwith each pass. By monitoring the tracks, the farmer can determine whichareas in the tracks present potential trouble spots that could benefitfrom the use of a foundation member in accordance with the presentinvention. Allowing a wheel track to reach depth of from 8 inches to 12inches before inserting a foundation member is probably a good idea, asa wheel track of that depth will assist in retaining the foundationmember in place, as will hereinafter be described.

One embodiment of foundation member in accordance with the presentinvention is illustrated in FIGS. 2, 3 and 4 and is identified by thenumeral 28. In this preferred embodiment, foundation member 28 comprisesa generally rectangular body or pad 29 of material having a top 30, abottom 32, a pair of opposite lateral sides 34 and 36, and a pair ofopposite ends 38 and 40. Preferably, pad 29 is constructed from asuitable synthetic resinous material such as, for example, high densityPolyethylene, although a number of other materials may be satisfactory.If pad 29 is constructed from high density Polyethylene, it mayadvantageously be injection molded.

Pad 29 has a thickness dimension of such magnitude that pad 29 is fairlyrigid. Although some flexibility is permissible, generally speaking pad29 retains its shape under heavy loading sufficient to keep a number ofthe pads interlocked with one another in a manner yet-to-be described.As will be seen, however, a second embodiment which does not useinterlocking means but is instead essentially of continuous length, canbe thinner and thus more flexible without departing from the principlesof the present invention.

While it may be possible that only a single foundation pad 29 isutilized at any particular trouble spot, it is likely that two or moreof the pads may be connected together to form a series in the wheeltrack. Thus, each pad 29 is provided with interlock structure broadlydenoted by the numeral 42 and including one or more male components 44at one end and a corresponding one or more female components 46 at theopposite end 40. In a preferred embodiment as illustrated in thefigures, a pair of male components 44 and a pair of female components 46are provided at opposite ends.

Each male component 44 is in the nature of a hook having a generallyoutwardly and longitudinally projecting top leg 48 and a downturned tang50 at the outer end of leg 48. Top leg 48 is slightly offset upwardlyfrom the remaining body of pad 29 which helps to create an angled recess52 below leg 48 and rearwardly of tang 50. In addition, the malecomponent 44 includes a keeper lip 54 that projects axially outwardlyfrom the lower end of tang 50 for use in keeping male component 44releasably locked within a corresponding female component 46.

Each female component 46 includes an opening 56 configuredcomplementally to a male component 44 for the purpose of releasablyreceiving and retaining component 44 when a pair of the pads 29 areinterlocked end-to-end. Thus, each opening 56 includes an undercutportion at its front extremity that defines an overhanging ledge 58. Atits rear end, each opening 56 has a transverse bar 60 that is slightlyrecessed with respect to the top surface of pad 29. Thus, as illustratedin FIG. 10, when a male part 44 is locked within a corresponding femalepart 46, part 44 is hooked over bar 60 as the latter is received byrecess 52. Tang 50 projects downwardly into and through opening 56,while lip 54 is trapped beneath overhanging ledge 58. Thus, the twointerlocked pads 29 are restrained against axial movement relative toone another by bar 60 and are restrained against vertical displacementrelative to one another by overhanging ledge 58. In effect, ledge 58 andlip 54 keep tang 50 hooked over bar 60.

Preferably, each pad 29 is perforated so as to present a plurality ofapertures 62. These allow water and soil to escape from underneath thepad when the pad is laid into a muddy wheel track. Apertures 62 alsohelp keep the pad in place within the wheel track and reduce thetendency for the pad to float up out of the bottom of the track. In onepreferred form, each pad 29 is 12 inches wide and 30 inches in length,which width works well in a wheel track made by a standard tire that is14.9 inches wide.

Installation and use of the foundation pads 29 is illustratedparticularly in FIGS. 11-17. As the tower begins to move down into aproblem area wherein the machine may get stuck on some future pass, oneof the pads 29 is placed on the downslope behind lead wheel 20 asillustrated in FIG. 11. In a preferred arrangement, pad 29 is orientedsuch that the female interlock parts 46 are closest to wheel 20 and maleinterlock parts 44 are the most remote from wheel 20. Then, as leadwheel 20 moves on down the slope and space permits, a second pad 29 isconnected to the first pad 29 using the vertical insertion/swing downlocking technique illustrated in FIGS. 5-8 (turned 180° from thosefigures). Additional pads 29 are added from right to left as lead wheel20 continues to move ahead until an appropriately long string of thepads has been created.

As illustrated in FIGS. 13 and 14, as wheels 20, 22 move through a wheeltrack 26 and enter a deep, muddy portion, the lead wheel 20 tends topush a surge 64 of mud and water ahead of it, which makes it difficultin that instance to place pads 29 in front of lead wheel 20. Thus, it isgenerally desirable to carry out the foundation installation processimmediately behind lead wheel 20 in a progressive right-to-left patternas described above. However, installing pads 29 behind, rather than infront of, lead wheel 20 is not a requirement, and in some instances itmay be desirable to place pads 29 elsewhere, depending upon the natureof the wheel track 26 and the conditions in front of lead wheel 20.

FIGS. 15 and 16 show a long string of installed pads 29. Any number ofpads 29 may be installed, as need be to meet the conditions at hand.Once installed behind lead wheel 20, the pads of the string are engagedand seated down into place by trailing wheel 22 as it moves down intothe problem area of the wheel track and becomes supported by the pads.As illustrated in FIG. 17, depending upon the width of each foundationpad 29, the lateral sides 34, 36 are relatively close to sidewalls 66and 68 of track 26, and the bottom 32 of pad 29 overlies the bottom 70of track 26. This positions pad 29 for use as a solid foundation withinthe otherwise soft portion of the wheel track and gives firm support towheels 20, 22 the next time they override pad 29. Hooking the padstogether in a string keeps the pads in alignment and allows them toassist one another in maintaining the proper position within the wheeltrack.

It will be appreciated that the pads 29 once installed within a wheeltrack may be left in place permanently or removed at the end of a seasonas may be necessary or desirable. As illustrated in FIG. 20, if removalis desired such operation is quickly and easily accomplished by simplypicking up one of the pads at the end of a series and lifting it out ofthe track, whereupon the other pads connected to the lifted pad willalso be stripped out of the track. The individual pads can then bereadily disconnected from one another if desired, or left in a connectedseries.

It has been found convenient to transport a number of pads to thetrouble site using the particular tower whose wheel track is to befixed. In this respect a lower, horizontally disposed structural pipe 72on the wheel tower 14 may be utilized to support a container full of thepads 29, or other arrangements can be made for supporting such a supplyof the pads.

It will be appreciated that pads 29 can be quickly and easily installed,and at a relatively low cost. Moreover, their use as a preventivemeasure keeps the irrigation machine from becoming stuck and causing theserious problems that are a natural consequence of such negativeoccurrence. If properly utilized, the pads in accordance with thepresent invention can prevent the frustrating situation wherein a singleisolated trouble spot in only one wheel track can shut down the entiremachine.

ALTERNATIVE EMBODIMENTS

FIG. 18 shows a second embodiment of a foundation member in accordancewith the present invention, such embodiment being denoted by the numeral128. In this embodiment, foundation member 128 takes the form of acontinuous ribbon or web 129 of material that may be cut to appropriatelength to accommodate the particular trouble spot involved. Preferably,ribbon 129 is constructed from a suitable synthetic resinous materialsuch as high density Polyethylene.

The foundation ribbon 129 is somewhat thinner than the foundation pad 29of the first embodiment and thus is not as stiff Preferably, ribbon 29is of such a thickness that it can be stored in a coil as illustrated inFIG. 18. To facilitate such coiling, one side of ribbon 129 may beprovided with a series of transversely extending grooves 130 that giveincreased flexibility to the ribbon. Preferably, ribbon 129 isperforated to present a plurality of apertures 162 for the same reasonthat apertures 62 are provided in pad 29.

Ribbon 129 has opposite straight sides 132 and 134 and is preferablyabout 12 inches wide. Thus, when a desired length of ribbon 129 isunwound from the coil and cut off, a generally rectangular piece isobtained that will fit down into the problematic wheel track and stay inplace. When the severed piece of ribbon 129 is in place within the wheeltrack, it is retained by the sidewalls of the track in essentially thesame manner as illustrated in FIG. 17 with respect to the foundation pad29.

A third embodiment of a foundation member in accordance with the presentinvention is illustrated in FIG. 19 and is denoted by the numeral 228.In this embodiment, foundation member 228 is blend of the first andsecond embodiments, taking the form of a series of individual pads 229interconnected by thinner, hinging lines of weakness 231 to form acontinuous strip. Pads 229 are thicker than ribbon 129 of the secondembodiment, and are similar in thickness to pads 29 of the firstembodiment. Although each pad 229 may be of any suitable length, it isbelieved that a length of about thirty inches is optimum, with a widthof about twelve inches. Preferably, foundation member 228 is molded froma suitable synthetic resinous material such as high densityPolyethylene, and each pad 229 is fairly rigid, as in the firstembodiment. Lines of weakness 231 permit member 228 to be coiled into aflat-sided coil for storage and transport, as with the secondembodiment. Apertures 262 help keep foundation member 228 seated withina wet, muddy track in the same manner as the first and secondembodiments.

To install foundation member 228, a desired length is unwound from thecoil and cut off at the appropriate line of weakness 231. When thesevered length is then inserted down in the problem area of a wheeltrack, it is retained by opposed sides of the track in the same mannerillustrated in FIG. 17 with respect to the first embodiment.

The inventor(s) hereby state(s) his/their intent to rely on the Doctrineof Equivalents to determine and assess the reasonably fair scope ofhis/their invention as pertains to any apparatus not materiallydeparting from but outside the literal scope of the invention as set outin the following claims.

1. In a method of irrigating a field using an irrigation machine that isprovided with a water supply conduit supported by a plurality of mobiletowers disposed at spaced locations along the length of the conduit,each of the towers having at least one load-bearing, ground-engagingwheel, the improvement comprising: running the machine in the fielduntil the at least one wheel creates a recessed wheel track in theground; inserting a foundation member into the wheel track in such amanner that a load-supporting surface of the member faces upwardly andthe foundation member is confined by opposite sides of the wheel track;and running the machine in such a manner that the at least one wheelrides on the foundation member when the at least one wheel is in thewheel track.
 2. In an irrigation method as claimed in claim 1, saidfoundation member comprising a generally flat pad having a top, abottom, a pair of opposite lateral sides, and a pair of opposite ends.3. In an irrigation method as claimed in claim 2, said pad havinginterlock structure at said opposite ends for releasably joiningtogether a plurality of the pads in a series.
 4. In an irrigation methodas claimed in claim 3, said interlock structure comprising a male parton one end and a female part on the other end.
 5. In an irrigationmethod as claimed in claim 1, said foundation member comprising a ribbonof material capable of being stored in a bulk roll and severed intodesired lengths.
 6. In an irrigation method as claimed in claim 1, saidfoundation member comprising a series of foundation pads integrallyinterconnected by thinner, hinging lines of weakness.
 7. In anirrigation method as claimed in claim 1, each of said towers including aleading load-bearing wheel and a trailing load-bearing wheel disposed torun in the same wheel track, said inserting step being carried outbehind the leading wheel and ahead of the trailing wheel.
 8. In anirrigation method as claimed in claim 7, further comprising the step ofinterlocking a number of the foundation members together in end-to-endrelationship.
 9. In an irrigation method as claimed in claim 8, saidinterlocking step being carried out within the wheel track.
 10. In anirrigation method as claimed in claim 1, further comprising the step oftransporting a supply of the foundation members on a mobile tower to thewheel track.
 11. A foundation member adapted for insertion into arecessed wheel track in the ground for supporting wheels of a mobileirrigation tower when the wheels are in the wheel track, said foundationmember comprising: an elongated, generally flat pad having a top, abottom, a pair of opposite lateral sides, and a pair of opposite ends;and interlock structure at said opposite ends of the pad for releasablyjoining together at least a pair of said pads in end-to-end alignment.12. A foundation member as claimed in claim 11, said interlock structurecomprising a male part on one end and a female part on the other end.13. A foundation member as claimed in claim 12, said male partcomprising a hook having an outwardly extending leg and a downwardlyprojecting tang at the outer end of the leg, said female part comprisingan opening for receiving said tang of the hook.
 14. A foundation memberas claimed in claim 13, said tang of the hook having a generallyoutwardly projecting lip at the lower end of the tang, said openingbeing complementally configured with respect to the hook to present anundercut, overhanging ledge disposed to overlie the lip when the hook islocked in the opening and thereby resist release of the hook from theopening.
 15. A foundation member as claimed in claim 14, said pad havinga plurality of apertures therein.
 16. A foundation member as claimed inclaim 11, said pad having a plurality of apertures therein.
 17. Afoundation member as claimed in claim 11, said pad being constructedfrom a synthetic resinous material.
 18. A foundation member as claimedin claim 17, said material comprising high density polyethylene.
 19. Afoundation member adapted for insertion into a recessed wheel track inthe ground for supporting wheels of a mobile irrigation tower while theyare in the wheel track, said foundation member comprising: an elongated,generally flat ribbon of material that may be severed into desiredlengths, said ribbon of material having a top side and a bottom side anda series of longitudinally spaced, transverse grooves in one of saidsides to permit the ribbon to be stored in a coil.
 20. A foundationmember as claimed in claim 19, said ribbon having a plurality ofapertures therein.
 21. A foundation member as claimed in claim 19, saidribbon being constructed from high density polyethylene.
 22. Afoundation member adapted for insertion into a recessed wheel track inthe ground for supporting wheels of a mobile irrigation tower while theyare in the wheel track, said foundation member comprising: a series offlat pads aligned in end-to-end relationship; and flexible lines ofweakness hingedly interconnecting the pads and integral therewith.
 23. Afoundation member as claimed in claim 22, said lines of weakness beingthinner than the pads.
 24. A foundation member as claimed in claim 22,each of said pads having a plurality of apertures therein.
 25. Afoundation member as claimed in claim 22, said pads and said lines orweakness being constructed from high density polyethylene.